text: The possibility of using unique properties of lanthanides in the nanotechnology is demonstrated. The origination of linear and nonlinear optical properties of lanthanide compounds with phthalocyanines, porphyrins, naphthalocyanines, and their analogs in solutions and condensed state and the prospects of obtaining novel materials on their basis are discussed. Based on the electronic structure and properties of lanthanides and their compounds, namely, optical and magnetic characteristics, electronic and ionic conductivity, and fluctuating valence, molecular engines are classified. High-speed storage engines or memory storage engines; photoconversion molecular engines based on Ln(II) and Ln(III); electrochemical molecular engines involving silicate and phosphate glasses; molecular engines whose operation is based on insulator – semiconductor, semiconductor – metal, and metal – superconductor types of conductivity phase transitions; solid electrolyte molecular engines; and miniaturized molecular engines for medical analysis are distinguished. It is shown that thermodynamically stable nanoparticles of LnM composition can be formed by d elements of the second halves of the series, i.e., those arranged after M = Mn, Tc, and Re.